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Cushing's disease (CD) is an endogenous hypercortisolism state caused by an adrenocorticotropic hormone (ACTH) secreting pituitary adenoma. Medical therapy is an important second-line treatment for CD. New pharmacologic agents for the treatment of patients with CD are under development. New possible intervention targets include various receptors and pathways in the corticotroph tumor, the hormone ACTH, and its receptor and enzymes involved in cortisone metabolism. This part of the article will focus on tailoring pharmacologic therapy according to patient specific characteristics, long-term medical therapy and development of new drugs for CD.

Cushing's disease (CD) is an endogenous hypercortisolism state caused by an adrenocorticotropic hormone secreting pituitary adenoma. CD is associated with vast comorbidities and has a significant detrimental effect on quality of life as well as longevity. First line treatment for CD is transsphenoidal surgery (TSS) while medical therapy is an important second line treatment in cases of TSS failure or infeasibility. Current existing medications for CD target different processes related to CD including the corticotroph adenoma, cortisol adrenal manufacturing mechanisms, and glucocorticoid receptor blockage and widely differ in advantages as well as adverse effects. In depth acquaintance with the specific characteristics of each drug is needed in order to provide patients with the appropriate therapy according to their specific needs.

BACKGROUND:Cyclic Cushing's syndrome (cCS) features fluctuating cortisol secretion, often causing diagnostic errors or delays, and possibly poorer outcomes. We aimed to identify unpublished cCS cases to characterise clinical challenges and guide strategies for improving outcomes by characterising cycle patterns, peak frequency, and evaluating complications. METHODS:This was a retrospective observational study at 43 endocrine centres in 21 countries, including patients with confirmed Cushing's syndrome showing two or more hypercortisolaemic peaks and one or more spontaneous eucortisolaemic or hypocortisolaemic trough. Data included both clinical (eg, comorbidities and physical signs of cortisol excess) and biochemical (eg, screening and confirmatory tests) parameters, imaging, treatment, complications, and outcomes. FINDINGS/RESULTS:Between Dec 1, 2023 and Feb 2, 2025, 116 potentially eligible patients were identified and 110 were included. Most patients were female (84 [76%] of 110 patients), with a median age at diagnosis of 44·0 years (IQR 31·8-58·3). cCS origin was pituitary in 70 (64%), ectopic in 25 (23%), adrenal in three (3%), and occult in 12 (11%). Cyclicity was primarily determined by 24 h urinary free cortisol, with median peaks of 7·40 × ULN (range 0·44-299) and troughs of 0·31 × ULN (0·02-0·98). The median peak count was 3·0 (IQR 2·0-4·0), mostly (55 [86%] of 64 patients) occurring at irregular intervals, and was most frequent and pronounced in ectopic cCS. Symptoms worsened in 87 (81%) of 108 patients during peaks and improved in 79 (74%) of 107 patients during troughs; 31 (28%) of 110 patients had spontaneous adrenal insufficiency. Bilateral inferior petrosal sinus sampling (BIPSS) was performed during troughs in 14 patients (18% of the 78 procedures done). Imaging missed tumours in 35 (32%) of the 110 patients, and nine (8%) underwent unwarranted surgeries at the wrong anatomical site due to misclassification. After 5·8 years (IQR 2·6-10·5) median follow-up, 55 (50%) of 110 patients had complete biochemical surgical remission, seven (6%) had spontaneous remission, 22 (20%) were medically controlled, six (5%) had partial remission, 11 (10%) remained uncontrolled, nine (8%) were lost to follow-up. During the entire observation period, 3% (3/110) died. Delayed diagnosis (45 [41%] of 110 patients) and therapy (47 [43%]) were also observed. INTERPRETATION/CONCLUSIONS:Even in specialised centres, cCS diagnosis and management remain challenging with high rates of spontaneous adrenal insufficiency, inappropriate surgeries, and poor outcomes. Ectopic cCS showed the most frequent and severe peaks. These findings might help to guide imaging localisations or the timing of BIPSS in patients with active occult ACTH-dependent cCS. Hypercortisolism needs to be biochemically confirmed before BIPSS to enable correct tumour localisation. Patients with suspected or proven cCS should be equipped with salivary cortisol collection kits to capture dynamic changes as well as being prescribed glucocorticoids to be used as a precaution. FUNDING/BACKGROUND:None.

CONTEXT/BACKGROUND:The biochemical diagnosis of carcinoid syndrome (CS) is established through the measurement of 24-hour urine 5-hydroxyindoleacetic acid (5-HIAA), but these measurements are prone to sampling error and may be troublesome for patients. Serum 5-HIAA measurements might constitute a more reliable and convenient alternative to diagnose CS. OBJECTIVE:To assess the diagnostic value of serum 5-HIAA measurements in patients with CS. DESIGN/METHODS:Retrospective cohort study. SETTING/METHODS:Tertiary care hospital. PATIENTS/METHODS:379 patients with a neuroendocrine tumor (NET), of whom 136 (35.9%) had CS, and 153 control samples were included. INTERVENTION/METHODS:Paired serum and 24-hour urine 5-HIAA measurements. MAIN OUTCOME MEASURE(S)/METHODS:Performances of serum and 24-hour urine 5-HIAA for the diagnosis of CS, measured by area under the receiver operating characteristics curve (AUROC). RESULTS:Serum 5-HIAA performance was similar to that of 24-hour urine 5-HIAA for the diagnosis of CS in the total NET cohort (n=379, AUROC 0.824 vs. 0.843, p=0.50) and in a subgroup of somatostatin analogue (SSA)-naïve patients (n=141, AUROC 0.915 vs. 0.938, p=0.66). Optimal cutoff value of serum 5-HIAA for the diagnosis of CS was 139.4 nmol/L (sensitivity 96.3%, specificity 87.6%) as determined in a subgroup analysis of SSA-naive patients with CS and controls. Serum 5-HIAA correlated well with 24-hour urine 5-HIAA (r=0.892, p<0.001) and the presence of flushing, diarrhea and carcinoid heart disease (OR 1.047-1.073 for every 100 nmol/L increase, p<0.001). CONCLUSIONS:Serum 5-HIAA measurements are equivalent to 24-hour urine 5-HIAA measurements for the diagnosis of CS in patients with NET and form an accessible alternative.

The majority of prolactinomas are treated with dopamine agonists (DA) with excellent response, however DA-resistance occurs in 10% of prolactinomas. Somatostatin (SST) receptors have been increasingly studied in prolactinomas. There are five SST receptor subtypes and a significant number of prolactinomas show expression of SST₅ and SST₁ mRNA. The somatostatin analog (SSA) pasireotide, which has 40-fold greater binding affinity to SST₅ compared to first-generation SSAs, shows promising results in case reports of DA-resistant prolactinomas. This two-center retrospective cohort study investigated the expression patterns of dopamine 2 (D2R), SST₂ and SST₅ receptors in surgical specimen of 34 patients with prolactinomas, 22 of which were DA-resistant. In vitro effects of cabergoline, octreotide and pasireotide on prolactin production was also examined in cultured prolactinoma cells. Receptor expression was scored using the immunoreactivity score (IRS). 31/34(91%) patients used DA preoperatively; 22/34(64.7%) were DA-resistant. Receptor expression in the cases was 97.1% for D2R, 70.6% for SST₅ and 41.2% for SST₂. In the majority of SST₂ positive cases SST₂ expression was very low. In in vitro studies comparing the effects of octreotide, pasireotide, and cabergoline on prolactin secretion, octreotide was the least potent drug and cabergoline was the most potent. SST₅ and D2R expression was highest in prolactinomas showing the highest response to pasireotide and cabergoline in vitro (median D2R IRS 1.0 vs 8.0 for < 50% vs. > 50% inhibition by cabergoline and median SST₅ IRS 3.5 avs. 12.0 for < 50% vs. > 50% inhibition by pasireotide). In a subgroup, pasireotide inhibited prolactin secretion with comparable potency to cabergoline. Targeting SST₅ with pasireotide may be a potential treatment modality for further clinical investigation in the treatment of a subset of DA resistant or intolerant prolactinomas.

First-line treatment of endogenous Cushing's syndrome (CS) is surgical removal of the tumor responsible for cortisol excess. However, medical therapy has an established role in treatment when patients are not surgical candidates or decline surgery, residual or recurrent disease is present and not amenable to repeat resection, and control of hypercortisolism is needed either preoperatively or while awaiting the effects of radiotherapy. The approach to medical therapy should be tailored based on the etiology, degree of hypercortisolism, and patient characteristics. Currently available medical therapy for all etiologies of CS either blocks adrenal production of cortisol or blocks its action at the level of the glucocorticoid receptor. Currently available medical therapy for Cushing's disease (CD) targets the adrenocorticotropic hormone-secreting pituitary tumor through activation of somatostatin and dopamine receptors, alkylating DNA damage, or immune system activation. More focused therapy with greater efficacy and fewer adverse effects is needed, particularly in the case of CD, with potential targets and drugs identified and in development.

CONTEXT AND OBJECTIVE/UNASSIGNED:The lack of efficacy of somatostatin receptor subtype 2 (SST2) preferring somatostatin analogs in patients with Cushing's disease (CD) results from a downregulating effect of hypercortisolism on SST2 expression. Our objective is to evaluate the efficacy of a strategy with sequential treatment of ketoconazole to reduce cortisol levels and potentially restore SST2 expression followed by octreotide as maintenance therapy in patients with CD. PATIENTS AND DESIGN/UNASSIGNED:Fourteen adult patients with CD were prospectively enrolled. Patients started with ketoconazole. Once cortisol levels were normalized, octreotide was initiated. After 2 months of combination therapy, patients were maintained on octreotide monotherapy until the end of the study period (9 months). Treatment success was defined by normalization of urinary free cortisol (UFC) levels. RESULTS/UNASSIGNED:). CONCLUSION/UNASSIGNED:Sequential treatment with ketoconazole to lower cortisol levels followed by octreotide to maintain biochemical remission according to UFC may be effective in a subset of patients with mild CD, suggesting that cortisol-mediated suppression of SST2 expression is a reversible process.

Non-mutational epigenetic reprogramming is considered an important enabling characteristic of neoplasia. Corticotroph tumors and other subtypes of pituitary tumors are characterized by distinct epigenetic profiles. The DNA methylation profile is consistent with disease-specific gene expression, which highlights the importance of epigenetic changes in tumor formation and progression. Elucidating the epigenetic changes underlying tumorigenesis plays an important role in understanding the molecular pathogenesis of corticotroph tumors and may ultimately contribute to improving tumor-specific treatment. Here, we provide an overview of the epigenetic landscape of corticotroph tumors. We also review the role of epigenetics in silencing the expression of tumor suppressor genes and promoting oncogenes expression, which could potentially be involved in the pathogenesis of corticotroph tumors. We briefly discuss microRNAs and epigenetic aspects of POMC regulation. Lastly, since the epigenetic changes are reversible, we discuss drugs that target epigenetic modifiers that could potentially be used in the arsenal of Cushing's disease treatment modalities.

The objective of this study was to establish recommendations for thromboprophylaxis in patients with endogenous Cushing's syndrome (CS), addressing the elevated risk of venous thromboembolism (VTE) associated with hypercortisolism. A Delphi method was used, consisting of 4 rounds of voting and subsequent discussions. The panel included 18 international experts from 11 countries and 4 continents. Consensus was defined as ≥75% agreement among participants. Recommendations were structured into the following categories: thromboprophylaxis, perioperative management, and VTE treatment. Consensus was reached on several critical areas, resulting in 14 recommendations. Key recommendations include: thromboprophylaxis should be considered at time of CS diagnosis and continued for 3 months after biochemical remission, provided there are no obvious contraindications. The standard weight-based prophylactic dose of low molecular-weight heparin is the preferred agent for thromboprophylaxis in patients with CS. Additionally, perioperatively and around inferior petrosal sinus sampling, thromboprophylaxis should be reconsidered if not already initiated at diagnosis. For VTE treatment, extended thromboprophylaxis is advised continuing for 3 months after Cushing is resolved. These Delphi consensus-based recommendations aim to standardize care practices and enhance patient outcomes in CS by providing guidance on thromboprophylaxis, including its initiation and continuation across various disease states, as well as the preferred agents to use. The panel also highlighted key areas for further research, particularly regarding the use of direct oral anticoagulants in CS and the management of mild CS and mild autonomous cortisol secretion. Additionally, the optimal duration of anticoagulant prophylaxis following curative treatment remains uncertain.